US5547016A - Method for heating a gas in a regenerator - Google Patents

Method for heating a gas in a regenerator Download PDF

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Publication number
US5547016A
US5547016A US08/232,064 US23206494A US5547016A US 5547016 A US5547016 A US 5547016A US 23206494 A US23206494 A US 23206494A US 5547016 A US5547016 A US 5547016A
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United States
Prior art keywords
regenerator
hot
cold
gas
heating
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Expired - Lifetime
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US08/232,064
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English (en)
Inventor
Hans-Georg Fassbinder
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LAir Liquide SA pour lEtude et lExploitation des Procedes Georges Claude
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LAir Liquide SA pour lEtude et lExploitation des Procedes Georges Claude
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Assigned to L'AIR LIQUIDE, SOCIETE ANONYME POUR L'ETUDE ET L'EXPLOITATION DES PROCEDES GEORGES CLAUDE reassignment L'AIR LIQUIDE, SOCIETE ANONYME POUR L'ETUDE ET L'EXPLOITATION DES PROCEDES GEORGES CLAUDE ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: FASSBINDER, HANS-GEORG
Priority to US08/639,005 priority Critical patent/US5690164A/en
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
    • F28D17/00—Regenerative heat-exchange apparatus in which a stationary intermediate heat-transfer medium or body is contacted successively by each heat-exchange medium, e.g. using granular particles
    • F28D17/005—Regenerative heat-exchange apparatus in which a stationary intermediate heat-transfer medium or body is contacted successively by each heat-exchange medium, e.g. using granular particles using granular particles
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
    • F28D17/00—Regenerative heat-exchange apparatus in which a stationary intermediate heat-transfer medium or body is contacted successively by each heat-exchange medium, e.g. using granular particles
    • F28D17/02—Regenerative heat-exchange apparatus in which a stationary intermediate heat-transfer medium or body is contacted successively by each heat-exchange medium, e.g. using granular particles using rigid bodies, e.g. of porous material

Definitions

  • the present invention relates to a method for heating a gas in a regenerator with a heat accumulation mass consisting of a loose bulk material arranged in a ring between two coaxial cylindrical grids, a hot collection chamber, surrounded by the inner hot grid, for the hot gases and a cold collection chamber, enclosed between the outer cold grid, on the one hand, and the external wall of the regenerator, on the other hand, for the cold gases, as well as a regenerator of this type.
  • the hot gases and cold gases are respectively conveyed radially through the heat accumulation mass, in contrast to air heaters which are otherwise usual, and actually during the heating phase, from the hot collection chamber inside the regenerator to the outer cold collection chamber, and in the opposite direction during the cold blowing of the regenerator.
  • the gases to be heated may also be gaseous mixtures, which also contain proportions of vapors, in particular water vapor.
  • a regenerator of this type is described in U.S. Pat. No. 2,272,108.
  • the quantitative embodiment, not given here, of the example of application which is given therein shows that a regenerator according to the description of this U.S. Patent would absolutely not operate in practice.
  • a qualitative evaluation furthermore demonstrates that the gas speed chosen for passing through the heat accumulation layer was chosen much too small and furthermore that the aforementioned size of the particles of the loose bulk material of the heat accumulation mass is too large. These values thus lead to a head loss of the gas which is too small in the material bed.
  • the pressure of the gas decreases with the height in the cold collection chamber, while this effect, also known by the term "stack effect", is negligible in the cold collection chamber.
  • the pressure difference caused by this "stack effect” is a multiple of the head loss in the material bed, with the consequence that, when heating the regenerator, the heating gases flow only in the upper region through the material bed while, in the lower region, back-flow might even be expected.
  • the regenerator described in U.S. Pat. No. 2,272,108 would fail entirely.
  • the object of the invention is therefore to improve the method mentioned in the introduction, as well as the regenerator described hereinabove, by avoiding the drawbacks generated by the stack effect and in particular by increasing the power of the regenerator, but with a constructional height of the latter which is markedly reduced.
  • this object is achieved by the fact that the increase in the head loss during the heating phase is at least 5 times as great as the product ⁇ .g.H, in which H is the height of the regenerator, ⁇ is the density of the gas at a temperature of 20° C. and g is the acceleration due to gravity, and that the gas flow rate is at least equal to 300 m 3 N/h.m 2 of surface area of the hot grid at standard pressure.
  • FIG. 1 is a graphical representation of the temperature distribution.
  • FIG. 2 is a regenerator apparatus suitable to carry out the invention.
  • the cold phase that is to say the cold blowing, is carried out with an overpressure.
  • the flow rate of gas to be heated increases in the ratio P/P 0 , without the heat transfer being adversely affected. If a blast furnace blast is produced, for example, under a pressure of 5 bar, the flow rate may reach 5000 m 3 N/h.m 2 , or 2500 kW/m 2 . With a regenerator having a grid surface area of 20 m 2 , a hot blast flow rate of 100,000 m 3 N/h may be produced.
  • the particle size of the loose bulk material is chosen to be less than 15 mm.
  • the heating phase when operating with partial load, is carried out at full power and pauses are made after the cold blowing phase.
  • This embodiment of the method makes it possible to work with the desired throttled power, and the thermal equilibrium of the two phases is then set up by the pauses after the cold blowing, and also to use, for heating the regenerator, a burner which has only a very limited setting range, in contrast to the burners hitherto used in conventional blast heaters.
  • the other object imposed on the invention is, in a regenerator intended for implementing the method, achieved by the fact that the external diameter of the annular heat accumulation mass is at most double the internal diameter.
  • This embodiment of the thickness of the heat accumulation layer influences the parameter ⁇ 2p already explained hereinabove.
  • This parameter is in fact small for a diameter ratio greater than that mentioned. Calculations and tests have shown that this ratio should not substantially exceed the value 2.
  • the regenerator is heated with a premix burner.
  • FIG. 2 One embodiment of the burner is represented in FIG. 2 and will be explained in detail hereinbelow.
  • the regenerator 1 intended for implementing the method of the invention has an enclosure 2 with the form of an upright cylinder, which may, for example, be supported using pillars 3.
  • the internal space of the enclosure 2 is essentially divided, by two grids 4 and 5 of cylindrical shape and arranged concentrically at a distance from each other, into an inner cylindrical hot collection chamber 6, an intermediate annular chamber 7 containing the heat accumulation mass consisting of loose bulk material, and a cold outer annular collection chamber 8 formed by the wall of the enclosure 2 with the grid 5.
  • inlets 10 have been provided for the heating gases which are produced by a premix burner 11, which is in turn fed by a gas/air mixing tube 12.
  • the hot inner collection chamber 6 ends, in the upper region of the enclosure 2 of the regenerator 1, in a hot blast outlet 13; the outer collection chamber 8 is connected to a chimney 14 for removing the burnt gases, from which the heating gases can escape after they have been passed through the heat accumulation agent in the intermediate chamber 7.
  • the gas/air mixing tube 12 is connected to a fan 15 which produces air both for the heating phase and for the cold blowing phase. In the heating phase, the air is conveyed by the gas/air mixing tube 12 and mixed with the heating gas, which has been introduced by the gas injector 16 into the gas/air mixing tube 12.
  • valves 17, 18 and 19 are closed, while the valve 20 as well as the outlet 13 are, in contrast, opened, so that the cold blowing phase can then start.
  • the open connectors are again closed and the previously closed valves are opened, so that the heating phase can restart.
  • the loose bulk material of the heat accumulation mass is composed of a charge of granules with a particle size which does not exceed 15 mm, and the external diameter of the annular heat accumulation mass is not greater than double the internal diameter.
  • this regenerator Although the heat accumulation mass of this regenerator is reduced to approximately one sixth of the heat accumulation mass of normal air heaters, having vertical circulation, which were hitherto used, the same quantity of heat energy is accumulated; this results from the S distribution of the temperature, according to FIG. 1.
  • This temperature distribution is fundamentally different from that of known air heaters, in which it is essentially linear.
  • the S distribution of the temperature provides two conclusive advantages compared to the linear distribution: on the one hand the temperature drop of the hot blast during the cold blowing phase is very small, and, on the other hand, the variation in the average temperature of the entire material bed is very high, of the order of 600° C.
  • the S distribution of the temperature also depends, however, not only on the prescribed particle size of the charge of granules but also on the minimum determined gas flow rate.
  • This minimum flow rate corresponds to a power of 300 m 3 N/h.m 2 .
  • the S profile of the temperature becomes increasingly pronounced.
  • a particularly advantageous operating point appears for a flow capacity of 1000 m 3 N/h.m 2 , a head loss of 1000 to 1600 pascal.
  • An increase in the flow rate up to 2000 m 3 N/h.m 2 is possible without decreasing the heat transfer, considering a head loss of 3000 to 5000 pascal. This power limit is applicable to running under normal pressure.
  • the flow rate can be further increased, virtually proportionately to the absolute pressure, without the heat transfer data being adversely affected. If, for example, a blast furnace blast is produced at 5 bar, the flow rate may reach 5000 m 3 N/h.m 2 , or 2500 kW/m 2 . A hot blast flow rate of 100,000 m 3 N/h can thus be produced with a regenerator having a grid surface area of 20 m 2 .
  • regenerator Because the heating of the regenerator is, in fact, generally carried out at normal pressure, three generators must be heated simultaneously, so that four regenerators are necessary in total in order to ensure continuous operation with a view to producing hot gases.
  • regenerators have a diameter of only 4 m with a height of 5 m, whereas air heaters of the same power, hitherto used, have a diameter of 8 m and a height of 30 m.
  • the pauses which are thus necessary for operation under partial head are preferably made after the cold blowing of the regenerator.

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Mechanical Engineering (AREA)
  • Dispersion Chemistry (AREA)
  • Chemical & Material Sciences (AREA)
  • Drying Of Solid Materials (AREA)
  • Air Supply (AREA)
  • Furnace Details (AREA)
  • Physical Or Chemical Processes And Apparatus (AREA)
  • Devices And Processes Conducted In The Presence Of Fluids And Solid Particles (AREA)
  • Air Bags (AREA)
  • Gas Burners (AREA)
US08/232,064 1992-10-29 1993-10-19 Method for heating a gas in a regenerator Expired - Lifetime US5547016A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US08/639,005 US5690164A (en) 1992-10-29 1996-04-16 Method and regenerator for heating a gas

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE4236619A DE4236619C2 (de) 1992-10-29 1992-10-29 Verfahren und Regenerator zum Aufheizen von Gasen
DE4236619.4 1992-10-29
PCT/FR1993/001025 WO1994010519A1 (fr) 1992-10-29 1993-10-19 Procede et regenerateur pour le rechauffage de gaz

Related Child Applications (1)

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US08/639,005 Continuation US5690164A (en) 1992-10-29 1996-04-16 Method and regenerator for heating a gas

Publications (1)

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US5547016A true US5547016A (en) 1996-08-20

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US08/232,064 Expired - Lifetime US5547016A (en) 1992-10-29 1993-10-19 Method for heating a gas in a regenerator
US08/639,005 Expired - Lifetime US5690164A (en) 1992-10-29 1996-04-16 Method and regenerator for heating a gas

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Country Status (10)

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US (2) US5547016A (de)
EP (1) EP0617785B1 (de)
JP (1) JPH07502804A (de)
KR (1) KR100317968B1 (de)
CN (1) CN1072793C (de)
AT (1) ATE247271T1 (de)
CA (1) CA2126993C (de)
DE (1) DE4236619C2 (de)
ES (1) ES2202314T3 (de)
WO (1) WO1994010519A1 (de)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5690164A (en) * 1992-10-29 1997-11-25 L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude Method and regenerator for heating a gas
US6389776B1 (en) 2000-03-14 2002-05-21 L'air Liquide Societe Anonyme A Directoire Et Conseil De Surveillance Pour L'etude Et L'exploitation Des Procedes Georges Claude Gas permeable refractory brick for use in regenerative heat exchanger and hot grid formed therefrom
US6631754B1 (en) 2000-03-14 2003-10-14 L'air Liquide Societe Anonyme A Directoire Et Conseil De Surveillance Pour L'etude Et L'exploitation Des Procedes Georges Claude Regenerative heat exchanger and method for heating a gas therewith
US20110035990A1 (en) * 2008-02-28 2011-02-17 Krones Ag Method and device for converting carbonaceous raw materials
US20110127004A1 (en) * 2009-11-30 2011-06-02 Freund Sebastian W Regenerative thermal energy storage apparatus for an adiabatic compressed air energy storage system

Families Citing this family (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4317947C1 (de) * 1993-05-28 1994-06-23 Atz Evus Verfahren und Vorrichtungen zur Umwandlung thermischer Energie eines Mediums in mechanische Arbeit
DE19521673C2 (de) * 1995-06-14 1998-07-02 Atz Evus Applikations & Tech Verfahren zur regenerativen Abluftreinigung
DE10039246C2 (de) 2000-08-11 2002-06-13 Atz Evus Verfahren zur Umwandlung von thermischer Energie in mechanische Arbeit
DE102004026646B4 (de) * 2004-06-01 2007-12-13 Applikations- Und Technikzentrum Für Energieverfahrens-, Umwelt- Und Strömungstechnik (Atz-Evus) Verfahren zur thermischen Entsorgung schadstoffhaltiger Substanzen
DE102007050566A1 (de) 2007-10-23 2009-05-07 Stevanović, Dragan, Dr. Verfahren und Vorrichtung zur Vergasung von kohlenstoffhaltigen Rohstoffen
DE102008014297A1 (de) 2007-11-16 2009-05-20 Krones Ag Verfahren und Vorrichtung zur Umwandlung kohlenstoffhaltiger Rohstoffe
AT506477B1 (de) 2008-02-21 2010-07-15 Schweighofer Franz Wärmespeichereinrichtung
DE102009011358A1 (de) 2009-03-05 2010-09-16 Krones Ag Verfahren und Vorrichtung zur Verwertung von Biomasse in einem Biomassen-Vergasungsprozess
DE102009038323A1 (de) 2009-08-21 2011-02-24 Krones Ag Verfahren und Vorrichtung zur Verwertung von Biomasse
DE102009038322A1 (de) 2009-08-21 2011-02-24 Krones Ag Verfahren und Vorrichtung zur Umwandlung thermischer Energie aus Biomasse in mechanische Arbeit
DE102013017010A1 (de) 2013-10-14 2015-04-16 Karl Brotzmann Consulting Gmbh Stromspeicherung über thermische Speicher und Luftturbine
CA2982255A1 (en) 2015-04-13 2016-10-20 Karl Brotzmann Consulting Gmbh Energy storage via thermal reservoirs and air turbines
DE102021108719A1 (de) 2021-04-08 2022-10-13 HiTES Holding GmbH Verfahren und Vorrichtung zur Umsetzung chemischer Energie eines Brennstoffes in Wärme und elektrische Energie
DE102021129812A1 (de) 2021-11-16 2023-05-17 HiTES Holding GmbH Verfahren und Vorrichtung zum Erzeugen von Wasserstoff
DE102021129804A1 (de) 2021-11-16 2023-05-17 HiTES Holding GmbH Verfahren und Vorrichtung zum Erzeugen von Wasserstoff
DE102021129810A1 (de) 2021-11-16 2023-05-17 HiTES Holding GmbH Verfahren und Vorrichtung zum Erzeugen von Wasserstoff
DE102022118858A1 (de) 2022-07-27 2024-02-01 HiTES Holding GmbH Thermisches Cracking von Methan oder Erdgas

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB387070A (en) * 1930-11-22 1933-02-02 Dougree Marihaye Sa Honeycomb structure for heat recuperating apparatus of the cowper type
US1940371A (en) * 1930-05-06 1933-12-19 Research Corp Apparatus for heating gases
US2272108A (en) * 1940-01-19 1942-02-03 Research Corp Regenerative stove
US4463799A (en) * 1980-10-29 1984-08-07 Agency Of Industrial Science Technology, Ministry Of International Trade & Industry Heat storage medium for latent heat thermal energy storage unit
EP0373450A1 (de) * 1988-12-10 1990-06-20 Klöckner Cra Patent Gmbh Verfahren und Regenerator zum Aufheizen von Gasen
US4943317A (en) * 1988-09-20 1990-07-24 Skw Trostberg Aktiengesellschaft Agent for desulphurizing iron melts, a process for the production thereof and a process for desulphurizing iron melts with the use of said agent
US4991396A (en) * 1987-03-27 1991-02-12 Webasto Ag Fahrzeugtechnik High performance burner

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4108744C1 (en) * 1991-03-18 1992-08-27 Atz Energie Umwelt Stroemungstechnik Gas heating jacketed regenerator with heat storage medium - has central chamber surrounded by layer of pebbles or granular material
DE4236619C2 (de) * 1992-10-29 1996-11-28 Air Liquide Verfahren und Regenerator zum Aufheizen von Gasen

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1940371A (en) * 1930-05-06 1933-12-19 Research Corp Apparatus for heating gases
GB387070A (en) * 1930-11-22 1933-02-02 Dougree Marihaye Sa Honeycomb structure for heat recuperating apparatus of the cowper type
US2272108A (en) * 1940-01-19 1942-02-03 Research Corp Regenerative stove
US4463799A (en) * 1980-10-29 1984-08-07 Agency Of Industrial Science Technology, Ministry Of International Trade & Industry Heat storage medium for latent heat thermal energy storage unit
US4991396A (en) * 1987-03-27 1991-02-12 Webasto Ag Fahrzeugtechnik High performance burner
US4943317A (en) * 1988-09-20 1990-07-24 Skw Trostberg Aktiengesellschaft Agent for desulphurizing iron melts, a process for the production thereof and a process for desulphurizing iron melts with the use of said agent
EP0373450A1 (de) * 1988-12-10 1990-06-20 Klöckner Cra Patent Gmbh Verfahren und Regenerator zum Aufheizen von Gasen

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5690164A (en) * 1992-10-29 1997-11-25 L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude Method and regenerator for heating a gas
US6389776B1 (en) 2000-03-14 2002-05-21 L'air Liquide Societe Anonyme A Directoire Et Conseil De Surveillance Pour L'etude Et L'exploitation Des Procedes Georges Claude Gas permeable refractory brick for use in regenerative heat exchanger and hot grid formed therefrom
US6631754B1 (en) 2000-03-14 2003-10-14 L'air Liquide Societe Anonyme A Directoire Et Conseil De Surveillance Pour L'etude Et L'exploitation Des Procedes Georges Claude Regenerative heat exchanger and method for heating a gas therewith
US20110035990A1 (en) * 2008-02-28 2011-02-17 Krones Ag Method and device for converting carbonaceous raw materials
US20110127004A1 (en) * 2009-11-30 2011-06-02 Freund Sebastian W Regenerative thermal energy storage apparatus for an adiabatic compressed air energy storage system

Also Published As

Publication number Publication date
WO1994010519A1 (fr) 1994-05-11
EP0617785A1 (de) 1994-10-05
CN1086895A (zh) 1994-05-18
DE4236619C2 (de) 1996-11-28
CA2126993C (fr) 2004-12-21
JPH07502804A (ja) 1995-03-23
CN1072793C (zh) 2001-10-10
ATE247271T1 (de) 2003-08-15
EP0617785B1 (de) 2003-08-13
KR100317968B1 (ko) 2002-04-22
US5690164A (en) 1997-11-25
DE4236619A1 (de) 1994-05-05
ES2202314T3 (es) 2004-04-01
CA2126993A1 (fr) 1994-05-11
KR940703990A (ko) 1994-12-12

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